Laserfiche WebLink
<br />. . <br /> <br />walked through the wa1k-ln campsites did not stress any sense of urgency, <br />did not warn of the danger that remaining in the area would entail, and <br />stated that 1 to 1-1/2 hours would be available for evacuation. A written <br />statement made by the ranger issuing the warnings substantiates the newspaper <br />report [28]. Two fatalities occurred at Aspeng1en Campground to people who <br />were last seen walking across the bridge into the walk-in (island) sites. <br />One person had been camped at a walk-in campsite. The other person was <br />attracted to the walk-in campsite area from a campsite within Aspenglen <br />Campground but outside of the area of significant flooding. Both deceased <br />campers had been informed of the impending flood (but not of a dam failure) <br />by other campers [2, 30]. <br /> <br />One way to assess the adequacy of the warning process quantitatively is <br />by comparing the potential versus actual number of lives lost among various <br />flood events or dam failures. Table 3 provides information which can be <br />used to judge the success of the warning process associated with the various <br />events discussed. The failure of the Buffalo Creek, West Virginia coal waste <br />dam in 1972 compares closely, in many respects, to the failure of Lawn Lake <br />Dam. Both caused flooding within a narrow valley about 15 miles long and, <br />both occurred shortly after daybreak. The Big Thompson flash flood of 1976 <br />resulted in damage starting a few miles downstream from Estes Park and can <br />also be compared to the Lawn Lake Dam failure. The topography of the areas <br />within the Big Thompson River which were flooded is very similar to Fall <br />River downstream from Cascade Dam. The Big Thompson flood occurred between <br />8 p.m. and midnight, which makes it somewhat d,ifferent from the Lawn Lake <br />failure. Approximately 60 percent of the survivors of the Big Thompson <br />flood received no warning. There were deficiencies in all three elements <br />of the warning process - detection, warning dissemination, and response _ <br />for the Buffalo Creek and Big Thompson floods. <br /> <br />Table 3. - Comparison of warnin~.success for three floods <br /> , ' <br /> Potential Actual Fatality <br />Event loss of life loss of life rate <br /> (approximate) (%) <br />Buffalo Creek Dam failure [3] 4,000 125 3.1 <br />Big Thompson flash flood [17] 2,500 139 5.6 <br />Lawn Lake Dam failure [20] 4,000 3 <0.1 <br /> <br />Factors Affecting the Success of the Warning <br /> <br />Many factors affected the outcome of the Lawn Lake flood. Some factors <br />promoted chances for a successful outcome, while others hindered success. <br />Some of the factors are beyond the control of public safety administrators <br />while others can be influenced to a greater or lesser degree. <br /> <br />6 <br /> <br />1 <br />